The fire season by the numbers

Fire agencies are preparing for the eclipse hordes, in the midst of a large fire season.

It’s mid-August, which means we’re nearing the peak of wildfire season in the West. This year started with grassfires and could end with an eclipse pilgrimage-sparked blaze — if the conditions are right (or rather, wrong). Here’s an overview of the 2017 season so far, by the numbers:

Wildfires have blazed across 6.4 million acres in the U.S. since the beginning of the year.

Over the last decade, the area burned by mid-August averaged 4.7 million acres. This larger-than-normal fire season kicked off with grassfires in places like the Great Basin, eastern Montana and southern California.

There are 56 large fires actively burning right now in the U.S.

Except for a single blaze in Florida, . Oregon hosts the most — 17 fires are burning there — while Alaska and Montana top the list in terms of total area burning. At least 119,585 acres are currently on fire in the last frontier, and 118,720 acres in big sky country. There are also across the nation.

California's 2010 Constantia Fire, fueled in part by cheatgrass.

California’s Sierra snowpack was 164 percent of average this winter.

All that moisture is what fueled some of the early rangeland fires. As snow melts in the spring, it nourishes what firefighters call “fine fuels,” grasses and small brush. This year’s exceptional crop of fine fuels fed the early-season fires, allowing flames to cover a lot of ground.

But wet winters can also delay the start of fires fueled by trees. That’s what has happened this year. Eventually, however, hot summer temperatures dried out the landscape, and large timber fires are now burning in the northern Rocky Mountains, Oregon and northern California.

One measure of particulate air pollution in Cheeka Peak, Washington, hit 208 micrograms per cubic meter on Aug. 3, among the country’s worst.

All those timber fires aren’t limited to the U.S. British Columbia is having a , which sent a thick haze of smoke over the Pacific Northwest in early August. Cheeka Peak, on the northwest corner of the Olympic Peninsula, normally has some of the state’s cleanest air, but its readings were beyond unhealthy. They before the smoke dissipated.

Between firefighters and support personnel, nearly 20,000 people are battling large fires.

of the “national preparedness” scale — level five. The level indicates the how much wildfire activity there is across the nation, and how many firefighters and other resources are devoted to fighting it. Level five means the wildfires currently burning could .

A firefighter builds fireline on the south edge of the Rice Ridge Fire in Montana.

Courtesy Lolo National Forest

At 46,000 acres, Oregon’s Nena Springs Fire is the largest blaze in the lower 48.

Human activity sparked the fire on August 8; strong winds caused it to grow quickly. , east of Salem on the Warm Springs Indian Reservation, was 40 percent contained as of press time.

In fact, humans cause 84 percent of wildfires in the U.S.

That’s why fire managers and researchers are concerned about the flood of people already descending on national forests and private lands across the West to witness the solar eclipse on Aug. 21. If it’s hot, dry and windy, an errant spark or a campfire improperly put out could easily trigger a blaze.

Of course, that’s true during a normal August, too. Still, the possibility of back roads clogged with extra campers and their cars has fire managers keeping fire-fighting aircraft and extra help at the ready.

A plane flies over the working Rice Ridge Fire in Montana, which spanned 12,861 acres as of August 18. The Rice Ridge fire was started from a lightning strike.

Courtesy Lolo National Forest

Oregon is expecting about 1 million visitors intent on viewing the celestial spectacle.

And Wyoming and Idaho could each see hundreds of thousands of solar sojourners. Fire restrictions and burn bans are already in place across much of the public lands that lie under the best eclipse-viewing areas, and national forests and other agencies are warning visitors of fire danger .

are burning along or near the path of totality, particularly in Oregon; many across Wyoming, Idaho and Oregon. Some campsites and trails have already been , stymying plans laid months ago.

The U.S. Forest Service established 6 remote firefighter camps within the Wallowa-Whitman National Forest in preparation for the eclipse.

If there is a fire, those satellite stations will make it possible for emergency personnel to respond quickly in spite of the road-jamming hordes. The Oregon Department of Forestry and the Bureau of Land Management also put up a handful of stations, to cover the national forest’s .

In addition to the remote camps, the agencies established several information stations and prevention patrols to let campers know about fire safety. They brought in extra fire planners and firefighters from out of state to help should an incident arise. There may be crowds of visitors in the national forest during the eclipse, but the management agencies overseeing the melee will have lots of extra people in the woods, too.